Nagpur: Nagpur choked on toxic air for half the summer, beating both Mumbai and Pune to become one of the most polluted cities in Maharashtra, as PM10 levels breached national safety standards on 46 days from March to May, the Centre for Research on Energy and Clean Air (CREA) stated on Tuesday. According to CREA, Nagpur emerged as the second most polluted in the state in May and the fifth in April. CREA analysis also found that two of Nagpur's four continuous air quality monitoring stations at GPO Civil Lines and Mahal consistently recorded PM10 concentrations above safe limits during the summer months. In November last year, the city was ranked the second most polluted in the state after Sangli, CREA stated. "While winter conditions trap pollutants close to the ground, summer brings a different challenge, with coarse particulate matter (PM10) remaining consistently elevated.